European Patent Application Publication Number 0 997 341 A1 provides a control device for a movable member. The control device includes a DC motor for establishing a transfer of the movable member in such a manner that after a first position of the moveable member is stored in a memory, even if the movable member is at a second position, the moving member is returned to the first position upon manipulating a switch. The control device also includes a motor pulse generating circuit for generating a cut-off frequency which is variable depending on a ripple pulse frequency which is indicative of a rotational number of the motor.
United Kingdom Patent Application Publication Number 2 060 944 A provides a seat position control device for a powered seat-adjusting mechanism for motor vehicles. The motor drives for the various adjustments each use of a motor with a predetermined number of poles. Thus, for each revolution of a motor, a predetermined number of pulses is generated. By counting these pulses and comparing them with a reference, the position of the seat can be determined. Within a memory, a desired location setting may be registered so that the seat can be returned to that setting when desired. A microprocessor is used as the logic and memory medium.